Grinding machine



5 Sheets-Sheet l M. H. ARMS ET AL GRINDING MACHINE Aug. 29, 1950 Filed Jan. 9, 1947 Aug. 29, 1950 M. H. ARMS ET AL GRINDING MACHINE 5 Sheets-Sheet 2 Filed Jan. 9, 1947 SN @Q iv o 0 .Q Q

mm N MN Aug. 29, 1950 M. H. ARMS ET AL GRINDING MACHINE 5 Sheets-Sheet 5 Filed Jan. 9, 1947 mwmk I I H W 1 i hmw, m \R w K L. m MN ll (\QQRN H Q Rwy a 1. .1 n w QN w iix 4% Q M. H. ARMS ET AL Aug, 29, 1950 GRINDING MACHINE 5 Sheets-Sheet 4 Filefd Jan. 9, 1947 Aug. 29, 1950 M. H. ARMS ETAL GRINDING MACHINE 5 Sheets-Sheet 5 Filed 7 Jan. 9, 1947 Patented Aug. 29, 1950 TE D S TATES PATEEN T O F F l C E GRINDING M-AGHINE Vermont Application Janu ry 194.7,, :Serial No. 721052 22 Claims.

This invention relates to grinding .machines and the like.

One object of the invention. is to provide improved mounting vof the work and tool carriages by which accurate .control and alinement of these parts is readily obtained and which is relatively insensitive to temperature changes and variations in temperature between Various machine parts.

A tur-tr er object is to provide improved mountings and controls by which accessibility of the work for inspection .or replacement is facilitated without requiring an extended motion of the parts to sufficiently separate the work and rindin wheel.

Still another object .of the invention is to provide {or automatic .a dj ustr;nent .oi the limits of trayerseas the end face of a grinding wheel employed for f c grinding is progressively r move ,hy wear and truing.

still another object is to provide an interlock net-ween face grinding stop mechanism and the pow r traver e me h ism so h t nly one of t ese may be n peration atone time.

eiurther vobject is t p de traversing mechenism for the traversing carriage y ich a nearly constant velocity throughout the traversing stroke may be obtained, which is particularly desirable when grinding lon holes, or a harmonic motion at high speed which is in some cases desirable when, grinding short holes.

Still another object is to provide a rigid support for the carriages when they are in grinding positions.

-Further objects and advantages will appear trom a description of an embodiment of the invention shown in the accompanying drawings in which Figures 1 and 2 areright end and front elevations, respectively, of a grinding machine embodying the invention.

Figure 3 is a sectional view on line 3-3 of Figure 2.

Figure 3a is a detail sectional view through the interlock valve in face grindingangular position.

Figure 3b is a detail sectional view on line ab-3b of Figure 3a.

Figures 4 to '7, inclusive, are detail sectional views on the correspondingly numbered section lines of Figure 3.

Figure 8 is a detailsectional view on line 8-8 of Figure 6.

Figure 9 is a fragmentary view partly in side elevation and partly central section through a wheel truing device.

Figure 10 is a fragmentary View partly in horizontal section through the work carriage moving mechanism.

Figure 11 is a detail sectionalview on line H-l l of Figure 10.

Figure 12 .is a detail sectional view on line 'l2 -l 2 of Figures .1 and .11.

,Figure 13 is a detail vertical sectional view on line l.3-l 3 of Figure ,3.

Figure 14 is a view similar to Figure .13, but showing the Work slide in ,facing position.

Figure 15 is .a .detail sectional view .on line l.5=--. l.5 .of Figure 13.

Figure 16 .is .a fragmentary view to alarger scale similar to .a portion of Figure .2 and show-- .ing the wheel carriage traverse mechanism.

Figure 160. is a view similar to .a portion of .Eieu-re l6, .but with ,parts shown .in difierent posi- :tions.

Figure 17 is adetail sectional view on line 1 I t-l1 .of Figure .16.

Figure ,18 is a detail sectional view on line -l-. 8-=-:l8 ofF-igu-re 17.

Figure 19 is a vvelocity space diagram illustrating the motion of the traversing carriage when the universal joint is set for straight line drive and where it is .set for an angular drive at As 'shownlloest in Figures 1 and. .2, this machine includes a bed i on which is mounted a pair of carriages .2 and .3, the carriage .2 being arranged to support .a'work spindle carrying a work :sup porting chuck 5 for a work piece 6., and the carriage 3. being :a tool carriage and as shown sup- ,.-por-ting a grinding wheel s indle i which carries lonits projecting end a grinding wheel 8.

Carriage amounting One portion .of the invention relates to the mounting of the two carriages 2 and '3. Each is supported on a pair of cylindrical guide bars 10 and II for the work carriage and I2 and 13 for the tool carriage. One of each of these guide bars is rigidly carried by the bed I, the guide bar It for the work carriage and the guide bar 12 for the wheel carriage being so shown. The guide bars I] and 13 are supported from a pair ofcarrier bars M and 15, respectively. "Each of these carrier bars is supported at opposite ends on vertically adjustable jack screws It (see Figure 6 for carrier .bar it support), and may be securedin vertically adjusted position as by screws I! passing through vertical slots in the respective carrier bars and threaded into the bed I By this means the carrier bars may be adjusted verticallyand independentl at each end. These carrier bars are arranged to support'at spaced points, reeds is which are rigidly secured at theirupper ends to the guide bars II or [3. The carrier barsv engage with: vertical faces I!) on the bed I and the planes of .flexure of the reeds are: perpendicular to the planes of the guide bars of the corresponding set, each set comprising a pair of guide bars Ill, H, and I2, I3. The reeds as shown. are in the planes of the central axes of the respective bars which avoids. any rolling effect of the bars as thereedsfiex.

, wide arm 33.

The carriages 2 and 3 are supported on the guide bars i and II and I2 and I3, respectively, on three sets of preloaded ball bearings, two sets of these bearings engaging one of the guide bars at spaced points therealong, and the other single set engaging the other guide bar of the pair. As shown, for example, two of these ball bearings at and 2| are engaged with the fixed guide bar It and a single such ball bearing engages the bar H. Similarly for the wheel slide, two spaced sets of such bearings are mounted on the bar [2, while a single set of such bearings is mounted on the bar [3. By this mounting the carriages may be moved freely along the guide bars in rectilinear paths and with maximum smoothness. The guide bars [0 and I2 which are provided with the pairs of spaced ball bearings are each provided with one support from the bed I located between these bearings as at Illa and |2a and a support I02) and |2b outwardly of one of these bearings. When the two carriages 2 and 3 are in grinding position,

the ball bearings for each are close to these supports of both bars, thus giving the most rigid support to the carriages for the grinding operation, and avoiding fiexure of the supporting bars which might otherwise occur. By reason of the reed mounting of one of the guide bars for each carriage and the independent vertical adjustment of each end of this guide bar transverse to the general plane of these guide bars, the guide bars of each pair may be adjusted into exact coplaner relation, and any variations due to temperature changes or to unequal temperature changes of various portions of the machine are taken up automatically by the flexing of the reeds. This mounting arrangement makes it easy to adjust the planes of motion of the two carriages in the desired precise relationships and to so maintain them during operations of the machine, and despite warping changes which may occur through seasoning of the bed and through temperature changes and variations of temperatures of different portions of the bed I. In order to protect the bearings on the guide bars from access by foreign materials, these bars may be surrounded by flexing bellows 255 which seal off these guide bars from their ends to the guided portions of the respective carriages.

The mounting of the carriages as thus described is not claimed per se herein but forms subject matter of a divisional application Serial No. 787,448, filed November 21, 1947, for Carriage Mounting.

Means are provided by which the wheelcarriage can be reciprocated. To this end the wheel carriage 3 has depending therefrom a lug 33 (see Figure 2) which may be connected through a link 3| to a lug 32 extending laterally from a This arm 33 is secured at its lower end to a rock shaft 34 journaled in the lower portion of the machine base. The upper end of the arm 33 has an extension 35 provided at its upper end with a handle 38 by the rocking of which the rock arm 33 is rocked, causing a traverse motion to be imparted to the slide 3.

Work carriage moving mechanism In order to facilitate access to the work piece when the wheel 8 is retracted and without requiring a long travel of the carriage 3, provision is made in accordance with this invention, for

. moving the work carriage laterally of the travel of the carriage 3 and as shown, forwardly, so that the work is brought out of its normal position \vhre the grinding wheel may operate upon the work and freely accessible to the operator. To this end, means are provided by which when the wheel car iage has been moved to retract the wheel from the work to a predetermined exclear of the work, the work head with its carriage is automatically moved forwardly. This means, as shown in Figure 10, may comprise a fluid actuated vane motor 43. As shown in Figure 13-, this motor comprises a cylinder within which is rockably mounted a vane i! fixed to a $1 at 3; coaxial with the motor 2-3. This vane may be moved angularly throughout substantially by fluid under pressure, such as compressed or hydraulic fluid, which may he delivered into the motor 5G through either of a pair of ports 63 and 44, the port not being employee. at any time for the supply of driving fluid being the discharge port. This vane motor is shown as attached to the work carriage 2. The shaft carries a crank G5 at its lower end, as shown best in Figures 1, 10 and 11, and this crank carries a connecting rod 66 pivoted between a pair of ears 6! projecting backwardly from the rear end of an axially movable nonatehle s w (Figure 13) on which is a a re feed sleeve 19 journaled in the ine frame and arranged to be turned ..l v by rotation of a feed shaft 493 connected thereto through interneshing gears 49! and 492.

ming the parts to be in the full line po- 10, and 11, the carriage 2 then being in back position with a stop abutment thereon engaging the forward end of the iced screw 28 as shown in Figure 13 and held. there by counterweight 29 (Figure 1) connected to the c 2 through a cable 555, fluid under pre delivered to the motor 40 throu h the pi e e2} will act to rotate the crank arm 13 ba rdly in a counter-clockwise direction as vie\.ed in Figure 10, this acting to move the carriage 2 forwardly of its normal working positicn, the carriage and the motor then taking the dotted line position shown in 3 Figure 10 and with the stop abutment 433 spaced vic regardless of the setting of the feed screw for fferent diameters.

Means r so actuating the vane mttor to produce the desired in .oments of the work carriage when the wheel is retracted or about to be moved into op rative position, is shown in Figure 3. The carriage 3 at its rear end is provided with a bracket 5i? from whi h projects an adjustable v' 5%. When the carriage 3 reaches a redetermined retracted position, this stop 51 engages the forward end of a valve stem 52 of a controlling valve In the position shown n Figure 3 where the carriage 2 is in its rear- .vard operative position, and the wheel carriage is in its working position, the stop 5! is out of contact with the valve stem 52, so that the spool valve is in the position shown, being pressed to the left as by the spring 55. Fluid under pressure conducted to the valve 53 through the pressure then passes around the valve 5 and through the pipe 44 and past a stantially a linear value is of substantial importance in grinding to close tolerances and it will be noted that this is produced without the use of elliptical gears or other complicated mechanisms which may result in an uneven or jerky motion of the carriage, and this arrangement makes possible any intermediate setting of the table to produce any desired intermediate velocity space diagram between harmonic motion, curve a, and the substantially straight 1ine motion shown in curbe b of Figure 16.

This power traverse mechanism is not claimed herein as it forms subject matter of a divisional application Serial No. 789,836, filed December 5, 1947, for Carriage Reciprocating Mechanism.

Facing mechanism and adjustments It is also possible with this machine to employ the grinding wheel for facing the work, and this is done in an intermediate position of the work carriage between the operative position shown in full lines in Figures 3 and 10 and the dotted line position shown in Figure 10, at which time the outer end face of the grinding wheel is opposite to a portion of the end face of the work. Where such facing is desired, the casing of the vane motor 40 is provided with an extension I50 (see Figure 12) which is bored to receive a piston valve II having a pair of spaced cannelures I52 and I53. The inner end of this valve extends into a recess I54 in the top end wall I55 of the vane motor and into the path of motion of an arm I60 clamped to the shaft 42 of the vane motor, and carrying at its outer end a roller I6I positioned to impinge upon the inner end of the valve I52 when the vane in the vane motor 40 is substantially midway of its end positions, this retracting the valve I5I against the pressure of a spring I62 engaging the outer end. When the valve I5I is in its norma'ly projected position, the cannelure I52 is interposed in the pipe 44 leading to one end portion of the vane motor, and a pipe connection IE3 is closed off from a discharge pipe I54. Between the vane motor 40 and the valve 54, the pipe 44 is provided with a branch I68 leading to the forward portion of the machine into a valve casing I shown best in Figures 3a and 3b. This casing I10 has a rocking valve I1I therein, which, when the valve I1I is in position for internal grinding, positions a lonr gitudinal passage I therein connecting the pipe I68 to a pipe I16 which joins the pipe 44. Thus when the wheel carriage is moved out of engagement with the valve 54 in the position shown in Figure 3, fluid pressure may pass the valve 54 not only directly into the left side of the vane through the pipe 44, but also through the branch pipe I68, the passage I15 of the valve HI, and the pipe I16 thereto.

When it is desi'ed to face grind, however, the valve I1I is turned to bring a passage I18 therein into the position shown in Figure 3a where the pipe I16 is connected to the pipe I63 which leads back to the valve I5I. As soon as the valve I5I is pushed rearwardly against the action of the spring I62 to bring the cannelure I53 in line with the pipes I53 and I64, the left hand side of the vane motor is opened through the pipe I16, the passage I 18 of the Valve I1I, the pipe I63, cannelure I53 of the valv I5I, and the pipe I64, to discharge. At the same time the right hand side of the vane is also opened to discharge through the pipe 43 and past the valve 54, so that both sides of the vane motor are now open to discharge and the motion of the vane motor stops.

At the same time that the valve I10 is thrown into the angular position which causes the stopping of the vane motor in its intermediate angular position, it throws down a stop bar I held by a forked arm I8 I, between a pair of abutments I82 and I83 as shown in Figure 14. The abutment I82 comprises a hardened plug seated in a fixed frame member I85, while the abutment I83 is yieldingly carried by the outer end wall of the work carriage 2. As shown in Figure 13, this abutment I83 in its normal backward springpressed limit of motion is arranged for micrometric adjustment in the line of travel of the work carriage. To this end it is shown as supported in a recess in the outer end of a plug I into which is threaded the extremity of a screw I9I. This screw I9I is provided with an enlarged diameter portion I92 which is threaded through a sleeve I94 clamped in the end wall of the carriage 2, one end of the sleeve I94 having an integral shoulder I95 and the other end having threaded thereon a locking collar I96. The outer end of the screw I9I is secured to a collar I98 by which it may be turned. ,The screw I9I may be a. differential screw, its two threaded portions being of slightly different pitch so that a very fine adjustment of the axial position of the abutment I03 may be afforded. A graduated disk 200 carried by the screw and cooperating with an index element 29I fixed to the carriage 2 will indicate to the operator the adjusted position. A shouldered element I99 threaded on the plug I90 and engaging the valve I1I for alinement limits the spring pressed position of the abutment I83 with respect to the plug I90.

As the stop member I80 is moved into position between the abutments I82 and I83, it serves to accurately define the mid-position of the carriage 2 at which the carriage will stop when the valve I 53 is moved to its rearward position. The work carriage then comes to rest in the mid-position suitable for face grinding, whereupon the wheel may be brought up to the work to face grind it by hand actuation of the feed lever 35.

However, in order that the proper facing position may be accurately determined. and this notwithstanding wheel wear and truing of the face grinding face, provision may be had for locking the wheel carriage in the proper axial positions, both for face grinding and for face truing of the grinding wheel. For this purpose mechanism shown best in Figures 3, 4 and 6 to 8 may be employed. In the frame of the machine there is axially movably mounted a threaded bar 2| 0. One end of this bar is threaded into a sleeve 2 (see Figure 8) which is journaled through a fixed bracket portion 2I2 and has secured to its outer end a retaining collar 2I3. This sleeve 2 is thus rockably mounted but is held against axial motion. Its outer end is provided with an actuating handle lever 2 by which it may be turned, and the amount of turning may be shown by index markings on the head portion 2I5 of the sleeve 2II in connection with a reference point 2I6 marked on the bracket portion 2I2. This bar 2I0 is keyed against turning motion, being provided with a key 220 engaging in a keyway 22I in a bearing portion 222 spaced from the bracket portion 2I2, and a spring 223 seated in an end socket therein and bearing against a cap plate 224 presses the element -2I0 axially to take up lost motion in its threaded connection with the sleeve 2I I. This bar 2I0 has a longitudinal keyway 225 therein within which ride keys 226 of a pair of abutment collars 221 and 228, each of which is provided with an abutment portion 229 and 230. These collars 221 and 2.28 may be adjusted ax ially of the bar 210 and secured in adjusted position by collars 232 threaded on the bar '2!!! and bearing against opposite faces of the collars :22] and 228. By adjustment of these collars 1232, it is evident that the spacing between the abutment collars 221 and 228 may be adjusted as desired.- The wheel carriage or slide .is provided with a latch hook 24$! .(see Figure 4) having a hookrecess 24! which may be engaged selectively on either of the abutments 229 or 230 andzs'hown in dotted line in Figure 4 as engaging the abutment 229. When the latch hook 240 is in engagement with this abutment .229, the end face of the grinding wheel is adjusted to be .in axial posit on to start face grinding of the work against which it may be fed by turning the hand lever .21 4 .in the proper .direction. When the latch hook 24a is in engagement with the abutment 239, the grinding end face of the wheel is removed from face grinding position and retracted to a point whereit is in position to be face trned. .A truing device 245 mounted on the work carriage-may :be employed for this purpose. This truing device is shown in Figures 3 and :9. It comprises a diamond holder 2510 adjustable axially in a sleeve 25!, this sleeve being pivoted at 252 on .a sup-port 253. It maybe rocked downwardly into the position shown in Figure 9 when thework carriage 2 is in grinding position, whereupon a diamond truing tool 254 is .in position to dress the periphery of the wheel, but in moving the truing device to this position, a second 'truing device 255 carried by an arm 256 secured to th holder 25f! sweeps across the end .face of the wheel as shown by the double arrow in Figure 9. .It will be noted that this trui-ng device 255 is positioned a fixed distance from the work carriage: in the direction of mot on of the wheel carriage, so that the abutment 230' :may be adjusted to bring the wheel face away from the work face to exact relation to the tuning device. Thuswhen the wheel carriage is retracted, and its latch hook 240 is engaged with the abutment 2311, it is in position for the truing device to be {brought downnto true its end face. As, .howeverg, this truing of the end face and also the wheel wear, removes the material of the wheel, the-latch may be movedalong the wheel carriage to move the wheel carriage toward the work carriage to compensate :for this as will later appear.

When the latch 24.0 is in -.engagement with either of the abutment-s2 -.or 230, this carriage should be disconnected from-the power traverse. Means are provided, therefore, for preventing the latch 62 from engaging the power traverse lever 69 when the latch hook 241i! engages either of the stops 229 .or 230;. To end, the latch 62 .is provided at its end remote from the hook .65 with an upwardly extending. arm .26!) and the latch 249 is provided with a similar upstanding portion-261. These'are arranged :torpro-iect above a table portion 262 which carries the pivot 63 for the hook162 and the pivot 263 for the hook- 2%, and in line with .these hooks are :axiall-y movable bars 266 and 261. .As :hest :shown :in Figure 8, these :bars 266 and 1261 are adapted to engage a. cam member Hui-carried bya vertical shaft 211i providedzwith an actuating ihandlelfm at its upper end. The cam member 2:10 is so formed that only :one of the bars-2B5 and .261 can be in anaxialtpositionat one time permit-- ting the corresponding hook to be in depressed position,.the rockingpf thexhandle 2T2 from=one angular positionto another acting to .raise .one

. forward; thewheel carriageis moved tdthedef't hook and allowing the other to descend. in intermediate position, both of these hooks areiin raised position and out of engagement with their respective cooperating members. .In this intermediate portion of the handle 2TH, the wheel carriage can be moved axially freely by manipulation .of the handle. 36. The table 2&2 which supports these hooks :may be adjusted in iine of motion of the wheel carriage with respect there-- to, and for this pur ose itis as shownbest in Figure- 7, as consisting of a slide having a dovetail toot 2'55 fitted between ways, :one .of which at 216 is adjustable, the slide 215 engag ing a lead screw 288 connected throughintermeshing spiral gears EM and 282 (see Figure .89 with an a djiis'ting shait -2 83 provided on thezouter face of the .carriage 3 a hand wheel 189. This adjustment compensates for grinding wear and 'tri-iing for the wheel face without changing the relation of the abutshents 229 and 230, the handle lever :2 and thegraduations- 215, the diamond holder,- and the face of the work.

setting up tdr face g rir-idi hg, he diamond point 255 is set at some shown-- tanee hem the finished face of the work. The lugs 22'!) and 259 are then spaced onthe threaded bar' 2W sothat the '(Sll- 'a'rloe-betweenthem is equa'ltd distancefrornthe diamond point to" the finished face of the work 'lYli-HHS-E'SafB allowance for stotik which is to be removed from the work, the aeg- 2-36- being adjusted first so that the face of the grinding wheel just contacts the diamond pointwhen the lug 230 is engagedby the latch 2-1!- andthe" lever 2M is at itsrearposition, prefer-'- a bly engaging a s'topil Md.

With thefiaiteh 2 4a engaging the lug 2 5e, the diamond 2515 is then broughtacross the face the grinding wheel, and-the wheel is fed-into t "e diamond by turning the kl-10b The i-ace (if wheel having been dresses; the diamond holder is swung :clear of th'e'whe'el and the m ss 2% is transferredto'thelug 229. This will-bring the ta e of the'grin'dingwheel"closeto the mo race-or a work piece. By swinging thelever 54' at a feeding rateunder control of the lever 2143 A positive stop 214'!" is provided" to 'l'imit'the" amount of axial feedby motion'of lever sit, or, if preferred, the graduations 2 15 maybe used to" determine when the proper'amount of stock has been removed. 35 following this method; the face of the work piece willj'b'e"held in'proper ,relaL tion with other fa'Ce'S OI" locating points or the work regardless'of wear "oi'the grinding wheel; which is compensated for automatically as the knob 289' istur'n'ed, and 'the'fa'c'e of the wheehis" d reiise'd Off in fixed rl'atidl'i tothe" finished sur faceof "the" work.

When the same wheel is used 'for" both hole and face grinding; the-cylindrical surface of t'he" wheel is shortened'as the" face-wears back; This means that the left hand edge""oi thewheeldoes not reachas'deeplyth-rough the hole, andin the case of a blind hole'i'nay' meantha't'th'e' wheredepth will not be groundunles's the-stroke ischanged to keep up-with this-Wear. This cor rection is accornplished'autornatically on thi's'ma--- chine since the wheel latch 6 2,- which is" used for the holegrinding'traversing stroke, is mount ed on the pivot-pin 263-Whidh is moved'to' com-- pensate for wheel- *fa'ce --wear, the position of the grinding=stroke beingalteredsimultaneouslywith the compensation forwhe'e'l face wear when use knob ZB-Misturned while-dressingtheiface of the wheel.

From the foregoing description of an embodiment of this invention, it should be evident to those skilled in the art that various changes and modifications might be made without departing from its spirit or scope.

We claim:

1. In combination, a support, a pair of carriages on said support mounted for relative rectilinear motions at substantially right angles to each other, one of said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for moving said tool carriage through a path of predetermined length to effect a traverse of said tool relative to the work and to extend such motion at predetermined times to retract the tool from the work in traverse, direction, and means actuated automatically when said tool carriage reaches a predetermined retracted position with said tool clear of the work to move said work carriage in its linear direction away from 9, normal tooling position to another position.

2. In combination, a support, a pair of carriages on said support mounted for relative sliding motions at substantially right angles to each other, one of said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for moving said tool carriage through a path of predetermined length to efiect a traverse of said tool relative to the work and to extend such motion at predetermined times to retract the tool from the work in traverse direction, and means actuated automatically when said tool carriage reaches a predetermined retracted position with said tool clear of the work to move said work carriage in its linear direction away from a normal tooling position to another position and for returning said work carriage to normal tooling position as said tool carriage is being returned from extended to normal tooling traverse.

3. In combination, a support, a pair of carriages on said support mounted for relative sliding motions at substantially right angles to each other, one of said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for moving said tool carriage through a path of predetermined length to effect a traverse of said tool relative to the work and to extend such motion at predetermined times to retract the tool from the work, means actuated automatically when said tool carriage reaches a predetermined retracted position to move said work carriage away from a normal tooling position to another position and for returning said Work carriage to normal tooling position as said tool carriage is being returned from extended to normal tooling traverse, said automatically actuated means including a crank arranged to approach a dead center position as said work carriage approaches normal tooling position.

4. .In combination, a support, a pair of carriages on said support mounted for relative sliding motions at substantially right angles to each other, one of said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for moving said tool carriage through a path of predetermined length to effect a traverse of said tool relative to the work and to extend such motion at predetermined times to retract the tool from the work in traverse direction, and means actuated automatically when said too carriage reaches a predetermined retracted position with said tool clear of the work to move said work carriage in its linear direction away from a normal tooling position to another position and for returning said work carriage to normal tooling position as said tool carriage is being returned from extended to normal tooling traverse, said automatically actuated means including mechanism slowing down the motion of said work carriage as it approaches either of its said positions.

5. In combination, a support, a carriage mounted for motion on said support, a feed screw, a nut journaled on said support and through which said screw is threaded, an abutment on said carriage normally contacting one end of said feed screw, means for rotating said nut to move said screw axially and thereby feed said carriage, and mechanism engaging said screw and carriage and operative to move said carriage relative to said screw in a direction to retract said abutm'ent from said screw to a predetermined dis-- tance and'to return said carriage to bring said abutment against said screw.

6. In combination, a support, a carriage mounted for motion on said support, a feed screw, a nut journaled on said support and through which said screw is threaded, an abutment on said carriag normally contacting one end of said feed screw, means for rotating said nut to move said screw axially and thereby feed said carriage, and mechanism engaging said screw and carriage and operative to move said carriage relative to said screw in a direction ta retract said abutment from said screw to a predetermined distance and to return said carriage to bring said abutment against said screw, said mechanism comprising a crank and link disposed in substantially dead center relation when said carriage is in either of its two positions.

7. In combination, a support, a carriage mounted on said support for motion in a rectilinear path, a member mounted for motion substantially in said path, power means for moving said member alternately in opposite directions, a releasable latch for connecting said member and carriage, a member adjustable lengthwise of said path, a releasable latch for connecting said adjustable member and carriage to lock said carriage in adjusted position, and means operative to release on of said latches when the other of said latches is to be made operable.

8. In combination, awork holder, a grinding wheel holder, means for relatively moving said holders in one manner to cause said wheel to face grind work carried by said work holder, and in another manner to cause said wheel to traverse the work, means for truing the end face of said wheel for fac grinding, means for limiting the traverse in the direction of approach of said end face, and means for automatically adjusting said traverse limit in accordance with the decreasing length of the face wheel as said end face is trued to cause said end face to reach the same limit of traverse on the work during the relative traversing motion of said holders regardless of such truing.

9. In combination, a support, a carriage mounted on said support for motion in a rectilinear path, a face grinding wheel mounted for rotation on said carriage, a Work holder toward and from which said carriage moves, a grinding wheel face truing device spaced from work on said work support in the direction of motion of said carriage and movable transversely of said direction to face dress said wheel when said wheel is spaced a predetermined distance from race or the work, an element mounted on said support par'ai' lei to said carriage motion, stops 'ad'justably spaced on said element one corresponding to the position of the work face and the other corre spending to the position of said truing device, means to lock said carriage to either selected or said stops to locate said wheel in face grinding or dining positions depending upon the stop to which said carriage is locked, and me ans for adjusting the endwise positions of both store simultaneously.

10. In combination, a support, a earria'ge mounted on said support for motion in a rectilinear path, a face grinding wheel mounted for rotation on said carriage, a work holder toward and from which said carriage moves, a grinding Wheel face-truing device spaced from work on said work support in the direction of motion of said carriage and movable transversely of said airetion to face dress said wheel 'whenfsaid wheel is s aced a predetermined distance fr m the face of the work, an externally threaded element mounted on said support parallel to said carriage motion, stops keyed to said element, collars threaded on said element on each side of said-stops "for adjusting and locking said stops in axially spaced relation corresponding to the position of the work face and to the position of Said t'rliing devie, respectivel means for locksa'id carriage to either selected or said stops to "locate said wheel in race grinding or trams positions, respectively, and means for adjusting said element exam to thereby feed Said wheel into the face of the work.

11. In combination, a support, a carriage mounted on said support for motion in a rectilinear path, a face grinding wheel mounted for rotation on said carriage, a work holder toward and from which said carriage moves, a grindiiig wheel face-truing device spaced from work on said work support in the direction of motion of said carriage and movable transversely of said direction to face dress said wheel when said wheel is spaced a predetermined distance from the'face of the work, an externally threaded element mounted on said support parallel to said carriage motion, stops keyed to said element, collars threaded on said element on each side o'f'said stops for adjusting and locking said stops in axially spaced relation corresponding to the position of the work face and to the position of said truing device, respectively, means for looking said carriage to either selected of said stops to locate said wheel in face grinding or truing positions, respectively, means for adjusting said element axially to thereby feed said wheel into the face of the work, and means for adjusting said locking means on said carriage lengthwise of said carriage motion to compensate for wheel face wear and truing.

12. In combination, a support, a pair of carriages on said support mounted for relative slid-- ing motion at substantially right angles to each other, oneof said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for moving said tool =carriage through a path of predetermined length to effect a traverse of said tool relative to the work and to extend such motion "at predetermined times to retract the 'tool from the work, "means actuated automatically when said tool carriage reaches a predetermined retracted position to move said work carriage away from a normal tooling position to another position, and

14 means for looking said work carriage in a posi tion intermediate to its normal and said other D' sitions 13. In combination, a support, a pair of carriag'e's on said support mounted for relative sliding motions at substantially right angles to each other, one of said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for moving-said tool carriage to effect a traverse of said tool relative to the work, a crank journaled on said work carriage perpendicular to its sliding direction, a link pivoted at oneend on said crank, an anchor member to which the other end of said link is pivoted, said member and crank journal being spaced in the sliding direction of said Work support, and means for rocking said crank to thereby move said work support.

14. In combination, a support, a pair of car'- riag'es on said support mounted for relative sliding motions at substantially right angles to each other, direct said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for moving said tool carriage to eifect a traverse of said tool relative to the work, a crank journaled on said work carriage perpendicular 'to its sliding direction, a link pivoted at one end on said crank, an anchor member to which the other end of said link is pivoted, said member and crank journal being spaced in the sliding direction of said work support, means for rocking said crank from one to another an ular position to move said work support between an operative and inoperative position, and a work feed mechanism connected to said anchor member for moving-said anchor member in the direction of .motion of said work support.

15. In combination, a support, a pair of carriages on said support mounted for relative sliding motions at substantially right angles to each other, one of said carriages supporting a tool and the other of said carriages supporting work to be operated upon 'by said tool, means for moving said tool carriage to effect a traverse of said tool relative to "the work, a crank journaled on said work carriage perpendicular to its sliding direction, a link pivoted at one end on said crank, an anchor member to which the other end of said link is pivoted, said member and crank journal being "spaced in the'sliding direction of said work support, 'r'n'eans for rocking said crank from one to another angular position to move said work support between-an operative and inoperative position, a feed screw carrying said anchor member,a feednut engaging said screw and jour'naled in said support, and means for turning said nut.

16. In combination, a support, a pair of car-- riages on said support mounted for relative sliding motions 'at'substan'tially right angles to each other, one of said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for mov-,

ing said tool carriage to effect-a traverse of said tool relative to the work, a crank journaledon said work carriage perpendicular to its sliding direction, a link pivoted atone end on said crank, an anchor member to which the other end of said link is pivoted, said member and crank journal being spaced in the sliding direction of said Work support, means for rocking said crank from one to another angular position to move said work support between an operative and inoperative position, a feed screw carrying said anchor member, a feed nut engaging said screw is and journaled in said support, and means for turning said nut, said carriage having an abutment alined with said feed screw and engaging the outer end of said feed screw at one limit of motion of said carriage as produced by rocking of said crank.

17. In combination, a support, a pair of carriages on said support mounted for relative sliding motions at substantially right angles to each other, One of said carriages supporting a tool and the other of said carriages supporting work to be operated upon by said tool, means for moving said tool carriage to effect a traverse of sa d tool relative to the work, a crank journaled on said work carriage perpendicular to its sliding direction, a link pivoted. at one end on said crank. an anchor member to which the other end of said link is p'voted, said member and crank journal being spaced in the sliding direct'on of said work support, means for rocking said crank from one to another angular position to move said work support between an operative and inoperative position, a feed screw carrying said anchor member, a feed nut engaging said screw and journaled in said support, means for turning said nut, a pair of alined abutinents one on said carriage and the other on said support, and a stop member interposable between said abutments to hold said car riage in a position intermediate to said operative and inoperative positions.

18. In combination, a support, a pair of can riages on said support mounted for relative slid.- ing motions at substantiall right angles to each other, one of sad carriages supporting a tool and the other of said carriages supporting work to be operated upon b said tool, means for moving said tool carriage to effect a traverse of said tool relative to the work, a crank journaled on said work carriage perpendicular to its sliding direction, a link pivoted at one end on said crank, an anchor member to which the other end of said link is pivoted, said member and crank journal being spaced in the sliding direction of said work support, means for rocking said crank from one to another angular position to move said work support between an operative and inoperative position, a feed screw carrying said anchor member, a feed nut engaging said screw and journaled on said support, means for turning said nut, a pair of alined abutments one on said carriage and the other on said support, a stop member interposable between said abutments to hold said carriage in a position intermediate to said opera tive and inoperative positions, and a micrometric' adjustment means for adjusting one of said abutments toward and from the other of said abutments.

19. A grinding machine having a pair of supports, means mounting one of said supports for motion from and toward the other of said supports, a work carrier on one of said supports, a grinding wheel carried by the other of said supports for operating on the work, means for moving the movable support including a rotary crank and a link operatively connecting said crank to said movable support, and means for adjusting the throw of said crank to adjust the amplitude of stroke of said movable support, the effective length of said link being adjustable to adjust the positions of said movable support at the limiting end portions of sa d stroke.

20. In combination, a support, a pair of carriages on said support mounted for relative rectilinear motion at substantially right angles to each other, one or said carriages supporting a tool and the other of carriages supporting work to be operated upon by said tool, means for mov'ng said tool carriage through a path of predetermined length to efiect a traverse of said tool relative to the work to extend such motion at predetermined times to retract the tool from the work in traverse direction, and means actuated automatically when. said tool carriage reaches a a redetermined retracted position with sa'd tool file of this clear of the work to' move said work carriage in one direction away from a normal tooling position to ano her position and for returning said work carriage in toe opposite d'recion to normal tooling position as said tool carriage is being returned from said extended to normal tooling acti .ted automatica ly when the tool carriage reaches predetermined retracted posit'on with said tool clear of the work to move said work carriage forwardly from a normal tooling posito facilitate access to the work.

22. In combination, a support, a pair of carriages on said support mo nted for relative rectilinear motion at 'substan y right angles to each other one forwardl and rearwardly and the other laterally, a tool supported by said laterally movable carriage, a work holder supported b said forwardly and rearwardiy movable carriage, means for moving said tool carriage through a path of predetermined length to e ct traverse of the tool relativeto work on said work holder and to extend such motion at times to retract the tool from the work in. traverse direction, and means actuated automatically when the tool carriage reaches a predetermned retracted position with said tool clear of the work to move said work cariage forwardly from a normal tooling position to facilitate access to the work and to return said work carriage to normal position as said tool carriage is being returned from extended to normal tooling traverse.

MERTON H. ARMS. PAUL A. GROBEY.

REFERENCES CITED "following references are of record in the UNITED STATES PATENTS Number Name Date 1,559,206 Van Norman Oct. 27, 1925 1,53 ,351 .Eieald et al. May 4, 1926 1,825,178 Kempton et al. Oct. 6, 1931 1,933,213 Guild Oct. 31,1933 1,997,978 Raule Apr. 16, 1935 2,027,627 Blood et al. Jan. 14, 1936 2,069 138 Feeney Jan. 26, 1937 2,083,682 Balsiger et a1 June 15, 1937 2,310,338 Arms Feb. 9, 1943 

